A conventional ratchet wrench 70 is shown in FIGS. 10 to 12 and generally includes a first recess 71 defined in the function end of the wrench 70 and a second recess 72 is defined radially in the inside of the first recess 71. Two flanges 73, 74 extend inward from the inside of the first recess 71, wherein the flange 73 includes a positioning groove 730 defined centrally therein. A first groove 75 and a second groove 76 are respectively defined between the conjunction portions of the first recess 71 and the two flanges 73, 74. The first and second grooves 75, 76 are partially and respectively in communication with the second recess 72. A ratchet wheel 71 is located in the first recess 71, and the second recess 72 accommodates a pawl and a spring which biases the pawl to be engaged with the ratchet wheel. When manufacturing the wrench 70, surplus material is formed at the conjunction portions between the first recess 71 and the first and second flanges 73, 74, so that the ratchet wheel cannot be smoothly operated. The first and second grooves 75, 76 are therefore made to remove the surplus material.
U.S. Pat. No. 7,044,029 discloses a wrench wherein the first recess has a groove defined in the mediate portion thereof and a C-clip is engaged with the groove. The C-clip has a rod extending perpendicularly to the axis of the first recess so that the spring has one end mounted to the rod and the other end of the spring contacts the pawl. However, the groove has to be made by further machining process which increases the manufacturing cost, and there are two further grooves have to be made in the inside of the first recess so as to remove the surplus material. In other words, there are three grooves defined in the inside of the first recess. Generally, the thickness of the function end of the wrench is 10 mm and the depth of the first recess is 6 mm. Three grooves have to be made within the 6 mm thickness of the inside of the first recess and this definitely reduces the structure strength of the function end. For a smaller scale wrench, the function end is less than 8 mm and the depth of the first recess is only 4 mm. Each groove requires 1 mm so that it is difficult to make three grooves in the 4 mm thickness of the inside of the first recess. The C-clip is located in the first recess and faces the wrench wheel, the C-clip is narrower and moves inward after a period of use, the C-clip directly contacts the ratchet teeth of the ratchet wheel and affects the operation of the ratchet wheel. The spring has to be mounted to the rod of the C-clip and this assembling step is difficult in the small space in the first recess. Furthermore, the spring has to be made to have a ring to be mounted to the rod, and this increases the manufacturing cost to the spring.
The present invention intends to provide a wrench which is easily manufactured and assembled.